In a current wireless network system, a function of a network device node is generally unchanged. After a device vendor sells a device to an operator, the device has a fixed network function, and if the device vendor does not update or upgrade the device, the network function of the device generally remains unchanged. Generally, the network device node is a wireless access point (AP).
Currently, in wireless communication, a network function is provided for a user service using a network as a center. A user can perform communication only using a network, a technology, and a network function that are supported in a current position. For example, a high-definition video conversation is used for a user service in a position. When the user service moves to a position in which a high-definition video conversation function is not supported, the user cannot carry on the high-definition video conversation any more.
However, when a network function is provided for a user service using the network as a center, and when the user service is switched from a source node to a target node in a moving process in the network, there is a possibility that a capability of the target node does not meet a current network function requirement of the user service. Therefore, the same network function cannot be obtained when the user service is switched from the source node to the target node, and further, consistent network-wide service experience cannot be provided for the user service on different nodes in the network.